Automatic chuck.



D. W. WOOD.

AUTOMATIC CHUCK.

APPLIOATION FILED MAYQ, 1912 Patented Dec. 9, 1913.

INVENTOR Zea/2'02 M25077 7460cZ ATTORNEYS WITNESSES DAVID WILSON V7001),OF BRAZIL, INDIANA.

AUTOMATIC CHUCK.

Specification of Letters Patent.

Patented Dec. 9, 1913.

Application filed May 9, 1912. Serial No. 696,091.

To all whom it may concern:

Be it known that I, DAVID "Wrnson VVoon, a citizen of the United States,and a res1- dent of Brazil, in the county of Clay and tate of Indiana,have invented a new and Improved Automatic Chuck, of which the followingis a full, clear, and exact description.

My invention relates to an automatic chuck and particularly relates to aholder to be used on turret lathes, screw machines, or wherever anautomatic chuck with a changeable collet is desired.

in the old form of chucks in which the holder is screwed on to athreaded spindle, the rear face of the chuck is so far removed from thefront work-carrying portion of the chuck, that any slight variation froma true engagement with the spindle would cause the front part of thechuck and the work carried thereby, to be materially off-com tered. Dueto the frequent detaching of the chuck from the threaded spindle and thechuck bearing on said spindle, a loose connection is made resulting in amaterial Wabbling which would throw the work out of true, causing extraoperations. In regard to the old style of chuck, it is noted that it isnecessary to temper the same, the heating operation of which frequentlydistorts the regularity of the threads, which causes the chuck to bindunevenly and often results in the oil-centering of the chuck and thework carried thereby.

I eliminate the above-noted objections by slidably mounting the colletin the spindle and centering the collet by a master, which master is inturn controlled by a hood in screw threaded engagement with the spindle.By this construction, the engagement of the hood with the spindle may bedisalined or worn without in any way affecting the alinement of thecollet itself.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar characters of reference indicatecorresponding parts in both the figures, and in which- Figure 1 is avertical transverse sectional view showing a preferred embodiment of myinvention, and Fig. 2-is an outside end view of the same.

Referring more particularly to Fig. 1, l have shown a hollow revolvingmember or spindle 3 driven from any suitable source, and shown mountedin bearings a, which bearings are in turn supported by a bracket 5forming part of the framework of the machine A. The working end of thespindle is prei'ierably enlarged to form a head 6, the outer end ofwhich head is recessed to form a pocket 7 concentrically disposedrelative to the bore of the spindle 3. If desired, a thrust collar 8 isinterposed between the head 6 and the bearings l.

Slidably mounted within the outer end of the bore'of the spindle andextending into the pocket 7, is a bored collet 9, which collet isrotated by the rotating spindle through a splined connection 10, andthis collet is adapted to be ejected from the spindle by means of a rearplunger 11, which plunger also acts to maintain the collet in engagement with the master hereinafter described. The collet is of generalcylindrical construction, the outer end of which is formed into afrusto-conical nose 19, extending from the outer edge of which noselongitudinally a material distance of the same, is a plurality of slots:21, shown in the illustration to be three in number. These slots permitthe collapsing of the collet when forced into engagement with themaster, to engage the work held between the parts of the nose 12.

Slidably mounted within the pocket 7 and conforming substantially to theconfiguration of the same and concentrically disposed relative to thecollet 9, is a collet master 13. This master has a centrally disposedfrustoconical bore adapted to engage the outside face of the nose 12, sothat a movement of the master into the pocket 7 will cause thecollapsing of the parts of the nose 12 and engage the work heldtherebetwcen.

In order to force the collet master into engagement with the split nose1?, the front recessed face lei of the master is engaged by the innerfront face 15 of a hood 16, which hood is of a general cylindrical forminternally screw-threaded at 17, which threads engage external threads18 on the head 6. The movement of this hood is eliminated because thespindle 6 contacts with the front recessed face 14]: at the inner frontface 15 of the hood 16. In order to rotate the hood on the spindle, thehood may be provided with a pair of diametrically spaced apart keyholes20 adapted to be engaged by a suitable lever key.

By the above outlined construction, it will be seen that the collet isrotated by the spindle 3 due to the splined connection there- 'tiontakes place between the hood and with, but, at the same time, it may bereadily concentrically disposed relative to the axis ejected from thespindle by the plunger 11 of said spindle, a collet slidably mountedafter the hood 16 has been removed, and a in said spindle and having afrusto-conical new collet may be inserted, or other work i split nosedisposed within the bore of said may be inserted in the old collet. Asthe master, and a hood in screw-threaded enhood 16 is not directly inengagement with gagement with said spindle and bearing on the collet, itis immaterial whether or notsaid master to force the same into said thethreads 17 and 18 are true, as any pocket, thereby to collapse the noseof irregularity in this threaded connection said collet, whereby thelatter may grip the would have no influence on the axial moveworkcarried thereby. ment of the master in the pocket 7. The 2. A chuckcomprising a rotatable spindle, collet master necessarily has a truemovea collet rotated by said spindle, a master enment parallel to theaxis of the spindle, and gaging said collet, and means carried by the solong as the outer face of the nose 12 and spindle and independent ofsaid collet, actthe inner bore of the collet master make ing on saidmaster to center said collet in true fits, it is immaterial what wearingacsaid spindle.

8. In combination, a hollow spindle having an enlarged head at one endthereof, said head having a bore communicating with the bore of saidspindle and concentrically disposed relative to the axis thereof, acylindrical master fitting within the bore of said head, said masterhaving a bore centrally disposed therein, said bore having an inclinedwall, a collet mounted within the bore of said spindle, said collethaving a nose fitting the bore of said master, and means inscrew-threaded engagement with said spindle, engaging said master tohold the same in engagement with said collet.

i. A chuck com arising a rotating spindle, a split nose collet carriedby said spindle, a member encompassing the split nose of said collet,and a member in screw-threaded engagement with said spindle, actingthrough said first-mentioned member to collapse the nose of said collet,thereby to bind the work in the same.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

DAVID WILSON WOOD.

Witnesses CYNTHIA BURKE, J AMES A. MONUTT.

spindle. In other words, as the movement between the master and thespindle is a sliding movement, and the movement between the master andthe collet is a sliding movement, there cannot be more wear on one sidethan on the other, so that having once centered the chuck, it willremain centered.

in chucking and rechucking work the master remains against the shoulderof the hood 16 and does not move back and forth in opening the chuck tofeed the stock hrough. But the collet being sprung gives a tension onthe nose so that when the latter is released it will shove back from themaster 13 causing the work to be freed and permitting the nose to bemoved forward for another operation, the collet being limited in itsbackward movement so that it will have a tension against the master 13to hold it against the hood 16.

Having thus described my invention, I claim as new and desire to secureby Letters Patent:

1. A ch ck comprising a hollow rotating spindle having a pocket at oneend, a collet master slidabl I mounted in said pocket, said colletmaster having a frusto-conical bore- Copies of this patent may beobtained for five cents each, by addressing the Commissioner of Patents,Washington. D. C.

